The Witness
by DArtagnan09
Summary: The moment Barry first realizes what he can do, someone else is there who sees it all. Unsure what else to do, he runs. In a place as big as Central City, he's sure he'll never see her again, right? ...Right? Barry/OC
1. Chapter 1

Don't worry, I'm still working on my Feeling Good 'verse, but inspiration is scarce.

This character just sort of grew in my head, and I was either going to put her with Barry or Spencer Reid. Barry's story with her manifested much more easily and naturally, so here it is. This will be a very small multi-chapter fic told in moments, beginning in the first episode. At least four short chapters, six tops. I hope you enjoy!

I don't own the Flash or anything else you recognize. Consider yourselves disclaimed.

* * *

"What is happening to me?"

Barry stared at the shattered glass on the police car, terror and awe waging a war inside him. This was impossible. This was insane. This was... _incredible_.

"Are you okay?"

Barry whirled around at the voice coming from the opening of the alley, forcing his movements to still, even as he couldn't help but look the girl over. She was young, probably around his age, pale blond bangs falling into blue eyes, the rest of her hair pulled back into a braid that dangled at her collar bone. Her denim skirt was short, but that was offset by the deep purple tights and knee high brown boots that covered her legs. Brights colors wound down both of her arms and creeped up her neck where her skin was exposed beneath her white tank top, and he could see metal glinting at her nose and eyebrow. For the first time he realized her eyes were wide open in shock, and his heart sank.

She had seen him. _Shit_.

He stood quickly, looking around for an exit, not seeing one besides right past her.

"Hey, it's fine! You don't need to be scared!" she insisted shakily, holding her hands up as though to show she was unarmed. She moved slowly towards him, like he was a skittish animal. He sort of felt like one. "You uh...you hit that wall...and car...pretty hard. Are you okay?"

She had seen a lot. _Double shit_.

That was it. He didn't have a choice. He surprised himself, and the girl from the look on her face, when he squeaked out a "Sorry!" before blurring past her in a rush of air.

He ran, marveling at what was happening to him even as he assured himself he'd never see her again in such a big city, though one thought niggled at the back of his head.

 _Why had he apologized?_

* * *

Second chapter will be up shortly, then I'd like to know what you guys think. I don't usually ask for reviews but I'm genuinely curious about how this character is being perceived both as an individual and as a pairing for Barry. I'll finish it regardless, likely within the next week or two, but the curiosity eats away!


	2. Chapter 2

Barry sees the girl again, and she becomes more mysterious.

I don't own the Flash or anything else you recognize. Consider yourselves disclaimed.

* * *

Central City was not, it seemed, as big a city as Barry thought, though it _was_ six weeks before he saw her again. This time he was enjoying a late night run through the streets when he was passing her almost before he noticed her.

It was the tattoos he noticed first, he realized, and he could inspect them closely this time. Both arms and hands were covered in fictional characters and scenes, from various mediums - he recognized at least three Doctors, two Sailor Scouts, and a swirl that was distinctly Starry Night. She was wearing a tank top again, despite the slight chill in the air, straight blond hair hanging loosely about her shoulders this time. Her skirt was dark green and fluttered at her knees, over short brown boots.

She was locking up what looked to be a storefront, but upon reading the sign on the glass door Barry realized it was a music school. He guessed she must be a teacher there, considering she had a key to the building and was leaving so close to midnight.

He was struck by the brief thought to stop and speak with her, but quickly shook that notion from his head. Hopefully she had dismissed what she had seen as impossible and forgotten all about it, there was no reason to prove it had been real. He wasn't even wearing his suit, just enjoying a leisurely jog. There was barely any lightning.

This entire mental cataloging and observation had taken scarcely a fraction of a second, but the decision to keep running was no sooner made than he found himself stopping in an alley around the corner, just out of sight. He froze when he heard footsteps running in his direction, and for some reason couldn't bring himself to move as she rounded the corner and saw him.

"It _is_ you! I told Kim she was imagining a red flash of lightning shooting past her, but part of me wondered...and it _is_ you!" She looked torn between feeling triumphant and confused, and somehow settled on unimpressed. "She made it sound like there was a lot more lightning."

"I wasn't exactly going all out," he defended himself without thinking. She looked as shocked as he did that he replied, before laughing.

"Well alright then. See you around." With a grin and a wave, she turned and left the mouth of the alley. Barry stood there for several seconds, unsure of what exactly had transpired, before following.

"Hey!"

She turned around, eyebrows raised. Barry swallowed once, then twice, asking himself the same question written all over her face.

 _What did he want?_

"Um. You're just...you're not even gonna ask?" She grinned at him again, and Barry couldn't help but stare at the dimple it made in her left cheek.

"Nah, it makes you more mysterious. Something to figure out. And it gives me an excuse to find you again."

"Again?" _She wanted to see him again? Why?_

"Yeah," she laughed, taking a few steps toward him. "I mean, I found you the first time. You found me this time. Seems like it's probably my turn, huh?"

"And how are you going to do that?" he asked, more boldly than he expected.

"Oh, trust me," she said, closing the distance between them and pressing a kiss to his cheek. "I'm sure I won't be able to stay away."

Barry was strangely satisfied by the pink tinge to her cheeks as she drew away, somehow just knowing that it had been an unusually bold step for her. He found himself grinning at her, and her eyes widened in shock a moment before she shyly smiled back, beginning to walk backwards away from him.

"So like I said. See you around." And then she had turned away from him, walking swiftly around the corner and out of sight.

Barry stood there for several more moments, both confused and satisfied by the encounter. The thought crossed his mind that he hadn't gotten her name, but he trusted that she'd find him sooner rather than later.

* * *

There was no clear way to include this as it's written from Barry's pov, but after Mystery Girl kisses Barry's cheek and he smiles at her, the reason she's kind of shocked is because she's blinded by his smile. Just a cute little tidbit. I hope you liked it!

It's bedtime for me right now, but I'll get at least two chapters up either before or after work tomorrow, and if that's not the end of it I'll have it finished hopefully within a week. Night guys!


	3. Chapter 3

Barry finally learns Mystery Girl's name.

I don't own the Flash or anything else you recognize. Consider yourselves disclaimed.

* * *

Their next meeting was sooner than expected, only a few days later, and unconventional even by their standards - it was in the precinct.

Barry was on autopilot coming down from his lab, eyes only on the coffeepot that waited in the main precinct. He didn't even glance around until his cup was full and the first sip had been taken, and only then did he allow his mind to focus on something else - namely the world around him.

He was surprised to see her sitting in one of the uncomfortable plastic chairs available to members of the public, scribbling on one of the clipboards provided for filling out reports and other paperwork. She must have succumbed to the cooler weather judging from the long purple sleeves covering her tattoos, and the dark jeans tucked into brown boots. The internal debate was startlingly brief before he was filling a second cup and walking over to her. She didn't appear to have noticed him, and he took a deep breath as he approached.

"I can't believe you tracked me down at work, you really are good." He kicked himself for how ridiculous he sounded, but when she looked up at him, the smile that spread across her face was so brilliant he thought sunglasses might not be a bad idea, then he kicked himself for the cheesy thought.

"I did say it was my turn. I can't take the credit, however - unfortunately, I'm here for something much more depressing than flirting with a handsome stranger." Her words were sincere, and he decided to take the opening where it was offered.

"My name is Barry Allen. It's nice to meet you..."

"Aggie Stone. It's nice to meet you too, Barry Allen." He held the second styrofoam cup out to her as he sat in the chair next to hers. "Oh! Thank you!" She took a sip, then smiled. "Black. You pass the first test."

"There are tests?" he played along. "And what's my next test?"

"Well that depends," she smiled, balancing the coffee and clipboard in one hand as she wrote with the other. "You work here? Any chance you're in the department that can get my student's stolen violin back?" She stopped writing to tuck her hair behind her right ear, revealing several hoops and studs lining the outer shell.

"Unfortunately not, I'm a CSI. My dad is a detective, though, I can see if there's anything he can do after you file your report."

"Oh, could you? That would be so wonderful - his mom barely speaks English, that's why I'm here filing the report for her. She spent all her savings on this instrument for him, I can't stand the thought of that going to waste."

"I'll ask him to make sure they know what's going on," he assured her. She smiled at him again and thanked him as she resumed filling out the report.

"So a crime scene investigator, huh?" Aggie asked, glancing up at him through eyelashes as pale as her hair. He was mesmerized by the way the blue seemed to hide behind the blond, and almost forgot to answer her.

"Yeah, uh, I really like science. I majored in chemistry and physics. And I get to help solve crimes."

"I hear that's not the only way you've been solving crimes," she said quietly, almost nonchalantly, but he saw her eyeing him from under her bangs as she signed the report.

He thought carefully before he answered. "I do like to use all the means at my disposal."

For some reason this made her throw her head back and laugh. "I bet you do, Barry Allen. So tell me - which of those means are you going to use to find me again?" She stood up without giving him the chance to answer, taking the paperwork she'd filled out to the desk and thanking the officer there before walking back to where he'd stood.

"Find you? Is it my turn again?"

"I admit, I'm not usually one for hard to get, but this is kind of fun, don't you think?" Aggie leaned in conspiratorially. "Will we, won't we? It's all _very_ exciting."

"Or you could just give me your phone number." She smirked up at him, exaggerating her dimple, and he could tell she saw his eyes go straight to it.

"You could just look at the report I just filed."

"That feels like cheating." And it did, he realized, and when he thought about it Aggie was making this cat-and-mouse back-and-forth pretty fun. She giggled.

"At least I'm not the only one enjoying this game. Find me one more time, Barry Allen, and you can have more than just my phone number." She kissed his cheek again before turning on her heel and leaving the precinct, throwing one last smile over her shoulder.

Joe had witnessed the tail end of the exchange, and raised an eyebrow at his foster son as he sidled up next to him. "And just who was that?"

"I'm not entirely sure," Barry said without thinking about it, and it was true - one moment she was bold, the next coy, the next shy, the next wildly flirtatious. It was making his head spin in a way he liked more than he thought he would, or even should. There was one thing he knew for sure, though. "But I'm going to find out."

* * *

And her identity is finally revealed! I hope you guys enjoyed!


	4. Chapter 4

And the game is drawing to a close.

I don't own the Flash or anything else you recognize. Consider yourselves disclaimed.

* * *

He didn't look up her phone number, and he didn't stop by the school where he knew she worked. It really did feel like cheating, and he had a feeling he was very close to the end of this game. Instead he gently reminded Joe about the stolen violin and went about his life as normal (or abnormal, as it were) for the next two weeks.

It was nearly closing time at Jitters and Barry was one of the last customers there, so his phone seemed unusually loud as it rang. "Hey, Joe," he said quickly after he'd answered. "What's up?"

 _"Hey Bar. I just wanted to let you know, Rollins and Lewis found that stolen violin at a pawn shop on the other side of town. They returned it to your friend's student about an hour ago."_

"That's great, Joe, thank you for letting me know! Tell Rollins and Lewis I said thank you as well."

 _"You got it Barry. See you son."_

Barry couldn't help but beam to himself as he hung up the phone and packed up the file he'd been working on, waving at the barista as he left. He hoped he'd run into Aggie soon to celebrate the news with her. He'd been thinking about her nearly nonstop for the past two weeks and was brimming with questions for her.

Where was she from? What was her favorite zombie movie? What kind of music did she teach? What kind of music did she listen to? Did she like spicy food? What did all of her tattoos mean?

He couldn't even find it in himself to be surprised when he saw Aggie leaving the library just before it closed, a stack of books in one arm as she began walking in the same direction he was, her back to him.

"Aggie!" He called out, waiting until she'd turned around and seen him, before glancing around. Seeing they were the only two on the street, he flashed to her side. She gasped, using one hand to hold down the skirt that had flared up around her bare legs, revealing more ink. Barry smiled at her sheepishly as she laughed.

"That is too cool, Barry," she said, shaking her head. "I've been hearing about your exploits all over town. If I'm being honest I'm keeping an ear out." She blushed as she admitted this, and Barry smiled wider.

"Have you talked to your student yet? The one whose violin was stolen?" Aggie cocked her head, confused.

"No, why do you...did they find it?" At his nod she threw her free arm around his neck in an awkward hug. "Oh, thank you Barry!"

He smiled as he returned the hug. "I didn't do anything except bug my dad about it, the officers did the work."

"Still, thank you," she said as she released him, looking up at him earnestly. "That's more than you had to do at all." They stood there smiling at each other for what was probably too long before Barry finally remembered how to use his mouth.

"What were you doing at the library?" he asked, taking the stack of books from her and offering her his other arm. She took it with a smile as they began to walk.

"Research. The owner of the music school where I teach wants to start a program for autistic kids. I don't have a lot of experience in that field so I was doing some studying. Apparently music is an excellent form of therapy for them, so that'll be exciting."

"What exactly is it you teach? Is it just violin?"

"The question is more like what _don't_ I teach - the best word for what I am would be savant."

"Savant?" Barry raised an eyebrow at her. She only shrugged, grinning shamelessly.

"Hey, you're a budding superhero, I need to play up my strengths where I've got them. And besides, it's not hubris, it's fact. Put any instrument in my hands and I'll master it in days, if it takes that long."

Barry whistled - she was being serious. "Most people with that kind of talent would be famous, not teaching."

"Horrible stage fright," she admitted in a stage whisper. "Let my students worry about impressing the audiences, all I have to do is make sure they're trying their best."

"You love it." It wasn't a question, it was written all over her face, the same expression he got when he ranted about science.

"They're so creative! I work mostly with fairly advanced students, usually teenagers. One of the rules at the school is you have to study at least two types of music, instruments, voice, it doesn't matter. Every week they form groups of four and cover a song - it can be a string quartet, a rock band, a barbershop quartet, anything they can think of. Last week, I heard a metal version of Prince Ali from the movie Aladdin. I still have goosebumps."

Their laughter echoed through the streets as they walked, before Aggie slowly drew them to a stop in front of a tall apartment building.

"This is me," she said, shy again as she looked up at him. It emboldened Barry as he set her stack of books on the low wall beside them, smiling at her.

"I believe I was told that when I found you again I'd get more than just your phone number." Aggie blinked up at him before she laughed, closing the space between them as she slid her arms around his neck.

"You are absolutely correct Mr. Allen," she all but whispered before pressing her lips against his. It was gentle and chaste, even as his arms wrapped around her waist, drawing her body flush against his. They pulled away slowly, resting their foreheads together, and Barry reached up to toy with one of the silver hoops at the upper shell of her ear. She almost purred, moving to nuzzle into his neck. Barry took a deep breath.

"Do you want to get some dinner?" She pulled away from him and smiled.

"There's an awesome twenty four hour diner around the next corner."

"Double bacon cheeseburgers?"

"Oh, now you're really talkin' my language, Barry Allen."

* * *

Nearly done. One, maybe two chapters to go. Enjoy!


	5. Chapter 5

Running into Aggie with the family, and learning a little more about her.

* * *

"So when are we going to meet Mystery Girl?"

In the few weeks since Barry had begun to date Aggie, he had told his family and friends how they'd met, leaving out the super speed parts for those not in the know. He was currently out with Joe, Iris, and Eddie, enjoying a short break at Jitters before Joe and Eddie had to get back to the precinct.

"I'm not sure," Barry answered Iris's question. "Soon, maybe? To be honest we don't really make plans so much as just sort of find each other regularly."

And it was the truth. They texted at least once a day, and once or twice a week just seemed to find themselves in each others vicinity. A few of these run-ins had led to actual dates, such as the movies or the time he made her dinner at her apartment as she studied teaching techniques.

"You're serious? And that works for you?" Joe asked.

Barry shrugged. "I mean we've always seemed to find each other at the right time...so...far..." And then he was laughing and shaking his head as he looked over his foster father's shoulder. "And I bet her ears are burning." His companions all turned to look at the young blond woman smiling and walking in their direction, realizing quickly that this was one of those times.

Barry had risen from his seat to meet her halfway, taking her gloved hands in his own and kissing her cheek. He spoke to her, gesturing back towards the table, and she nodded, still smiling. She began to remove her gloves and scarf as he led her back to the table, pulling an unused chair next to his own.

"Aggie, this is my foster dad Joe, my foster sister Iris, and her boyfriend Eddie. Everyone, this is Aggie." They couldn't help but stare at the tattoos on her hands as she shook theirs, and were further surprised when she removed her jacket to reveal more ink snaking up her arms and under the sleeves of her tshirt.

Aggie, used to this kind of staring, only smiled at them all. "So, you're family _and_ you're cops. Let the interrogation begin."

Barry opened his mouth to protest, but Iris immediately shot off with a stream of questions, soon joined by Joe and Eddie, and Aggie took it all in stride, answering honestly and cheekily when called for, sending Barry to get her a coffee. Within minutes they had pulled all sorts of information from her, such as

Her full name was Agnes Clyde Stone and she was 27 years old, only two years older than Barry. She had a twin sister named Hazel Bonnie Stone, now Matthews. She was raised in Montreal until she was six and moved to Central City when her father died, and neither sister could remember any French. She crocheted and watched horror movies in her free time. She had three cats, brothers named Arthos, Porthos, and Aramis. Her favorite instrument was the piano. She had a deep, unyielding love for Phil Collins and Peter Gabriel.

After a chuckle around the table - that one had been new to Barry, too - Joe rested his chin in his palm, looking at her. "I gotta ask, kid - what's with all the tattoos?"

Aggie smiled, leaning forward on her elbows. "Some of them tell a story about important times in my life. Some of them are art and things that I love. Some of them are just pretty. All of them reflect something of who I am, and of the the artist who did them. I'm also very particular about my tattoo artists. All of this work has been done by only four artists, because this is a kind of living art, and if someone is going to put a piece of themselves in my skin I need to know that they're people I can appreciate and respect as human beings. In a lot of ways I consider it an honor."

There was a collective hum of understanding, and Barry reached over to grasp her hand on the tabletop. Aggie smiled at him, before grinning back at his family.

"Also they make me look like a total badass."

* * *

This is probably it. I hope you liked it!


End file.
